This invention relates to a fluid infusion device such as hypodermic syringes and particularly to automatic mechanically-powered infusion devices.
The prior art discloses various mechanically-powered hypodermic syringes for medical or laboratory purposes. U.S. Pat. No. 3,886,938 to Sabo and Del Geurcio, which issued June 3, 1975 discloses a device which applies a driving force to a syringe under the control of conventional spring driven clockwork gear trains through a rack and pinion mechanism and is typical of the prior art in this area. In contrast to the present invention wherein a clockwork mechanism is mounted parallel to the overall length of the syringe, the clockwork mechanism of Sabo et al employs a rack and pinion gear in tandem with the syringe thereby increasing the overall length of the unit. In portable infusion devices, the increased length is a definite disadvantage and even in stationary devices, the overall unit size is a definite design consideration.
U.S. Pat. No. 2,764,980 to W. R. Smith which issued Oct. 2, 1956 discloses a continuous injection machine employing a reciprocating rack coupled to a hypodermic syringe. This disclosure is particularly suited for operating multiple syringes in a laboratory environment. Another prior art disclosure, U.S. Pat. No. 3,279,653 to F. W. Pfleger, which issued Oct. 18, 1966, discloses an escapement-controlled dispensing apparatus of a rather complicated type including drums and pulleys.
Prior art U.S. Pat. No. 3,685,967 to Caslow et al discloses a portable infusion pump for injecting fluids from a collapsible receptacle over an extended period of time. This patent does not employ a typical escapement mechanism but the pump is, nevertheless, controlled by a force constant spring which in turn is regulated by a timing device.
Further prior art of interest includes U.S. Pat. No. 2,498,652 to G. B. Glass which issued Feb. 28, 1950, U.S. Pat. No. 3,605,765 to P. Koltzman which issued Aug. 5, 1952 and British Patent 1,026,593 which was published Apr. 20, 1966. None of these prior art patents appear pertinent to the clockwork driven syringe of the present invention which contains unique features facilitating the widespread adoption of the device. Notably, the present invention is relatively small and portable due to the internal construction thereof, comparatively simple to manufacture, and inexpensive.
Accordingly, an object of this invention is to provide a new and improved mechanically powered syringe for the infusion of fluids into individuals.
Another object of this invention is to provide a new and improved portable clockwork driven syringe which is small in size and efficient in operation.
A more specific object of this invention is to provide a new and improved clockwork driven syringe which includes a unique two-way clutch which aids the mounting of the clockwork mechanism parallel to the syringe thereby lessening the overall size of the device.